MESOSCALE DISCUSSION 1695
   NWS STORM PREDICTION CENTER NORMAN OK
   0645 PM CDT MON JUL 27 2009
   
   AREAS AFFECTED...NE IA...SE MN...S WI
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 629...
   
   VALID 272345Z - 280115Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 629
   CONTINUES.
   
   SEVERE THUNDERSTORMS...INCLUDING A FEW SUPERCELLS...CONTINUE IN
   SEVERE THUNDERSTORM WATCH 629...WITH A THREAT FOR AN ISOLATED
   TORNADO OR TWO. CURRENT SFC ANALYSIS INDICATES THAT STORMS ARE
   PERSISTING ALONG AN INSTABILITY AXIS THAT STRETCHES FROM A MLCAPE
   MINIMUM OF AROUND 500 J/KG IN SHEBOYGAN COUNTY WISCONSIN...TO A MAX
   OF AROUND 2500 J/KG IN VERNON COUNTY IOWA. LATEST IR IMAGERY SHOWS
   CLOUD TOPS ASSOCIATED WITH THE STRONGER STORMS /SUPERCELLS/ HAVE
   COOLED SIGNIFICANTLY IN THE PAST COUPLE OF HOURS...INDICATING STORM
   UPDRAFTS HAVE STRENGTHENED AND ARE AT PEAK INTENSITY. AS THESE
   STORMS REMAIN IN THE AREA OF THE MODERATE INSTABILITY AXIS...WHERE
   0-6KM SHEAR IS ALSO MAXIMIZED AROUND 30 TO 35 KTS...THE THREAT FOR
   ROTATING STORMS WILL CONTINUE FOR AT LEAST THE NEXT COUPLE OF
   HOURS...THROUGH PEAK DIURNAL HEATING. STORMS ARE EXPECTED TO SLOWLY
   WEAKEN WITH SOUTHEASTWARD MOVEMENT INTO SOUTHERN WISCONSIN...WHERE
   OBSERVED INSTABILITY WEAKENS RAPIDLY IN SOUTHEAST WISCONSIN.
   
   ..LEVIT.. 07/27/2009
   
   
   ATTN...WFO...GRB...MKX...ARX...MPX...
   
   LAT...LON   44529284 43979288 43489285 43079285 42999199 42919115
               42839050 42758971 42638897 42538802 42488775 42678772
               42998772 43288772 43508774 43938777 43998822 44098900
               44219001 44289069 44359126 44429192 44519268 44519284
               44529284